A novel magnetic levitation support method is proposed, which can relieve the perturbation caused by traditional support methods andprovide more accurate position control of the capsule. This method can keep the perfe...A novel magnetic levitation support method is proposed, which can relieve the perturbation caused by traditional support methods andprovide more accurate position control of the capsule. This method can keep the perfect symmetry of the octahedral spherical hohlraum and hasthe characteristics in stability, tunability and simplicity. It is also favorable that all the results, such as supporting forces acting on the super-conducting capsule, are calculated analytically, and numerical simulations are performed to verify these results. A typical realistic design isproposed and discussed in detail. The superconducting coating material is suggested, and the required superconducting properties are listed.Damped oscillation of the floating capsule in thin helium gas is discussed, and the restoring time is estimated.展开更多
In this paper, a bias-eliminated subspace identification method is proposed for industrial applications subject to colored noise. Based on double orthogonal projections, an identification algorithm is developed to eli...In this paper, a bias-eliminated subspace identification method is proposed for industrial applications subject to colored noise. Based on double orthogonal projections, an identification algorithm is developed to eliminate the influence of colored noise for consistent estimation of the extended observability matrix of the plant state-space model. A shift-invariant approach is then given to retrieve the system matrices from the estimated extended observability matrix. The persistent excitation condition for consistent estimation of the extended observability matrix is analyzed. Moreover, a numerical algorithm is given to compute the estimation error of the estimated extended observability matrix. Two illustrative examples are given to demonstrate the effectiveness and merit of the proposed method.展开更多
Introduction To compare the perfusion volumes assessed by a new automated CT perfusion(CTP)software iStroke with the circular singular value decomposition software RAPID and determine its predictive value for function...Introduction To compare the perfusion volumes assessed by a new automated CT perfusion(CTP)software iStroke with the circular singular value decomposition software RAPID and determine its predictive value for functional outcome in patients with acute ischaemic stroke(AIS)who underwent endovascular treatment(EVT).Methods Data on patients with AIS were collected from four hospitals in China.All patients received CTP followed by EVT with complete recanalisation within 24 hours of symptom onset.We evaluated the agreement of CTP measures between the two softwares by Spearman’s rank correlation tests and kappa tests.Bland-Altman plots were used to evaluate the agreement of infarct core volume(ICV)on CTP and ground truth on diffusion-weighted imaging(DWI).Logistic regression models were used to test the association between ICV on these two softwares and functional outcomes.Results Among 326 patients,228 had DWI examinations and 40 of them had infarct volume>70 mL.In all patients,the infarct core and hypoperfusion volumes on iStroke had a strong correlation with those on RAPID(p=0.68 and 0.66,respectively).The agreement of large infarct core(volume>70 mL)was substantial(kappa=0.73,p<0.001)between these two softwares.The ICV measured by iStroke and RAPID was significantly correlated with independent functional outcome at 90 days(p=0.009 and p<0.001,respectively).In patients with DWI examinations and those with an ICV>70 mL,the ICV of iStroke and RAPID was comparable on individual agreement with ground truth.Conclusion The automatic CTP software iStroke is a reliable tool for assessing infarct core and mismatch volumes,making it clinically useful for selecting patients with AIS for acute reperfusion therapy in the extended time window.展开更多
文摘A novel magnetic levitation support method is proposed, which can relieve the perturbation caused by traditional support methods andprovide more accurate position control of the capsule. This method can keep the perfect symmetry of the octahedral spherical hohlraum and hasthe characteristics in stability, tunability and simplicity. It is also favorable that all the results, such as supporting forces acting on the super-conducting capsule, are calculated analytically, and numerical simulations are performed to verify these results. A typical realistic design isproposed and discussed in detail. The superconducting coating material is suggested, and the required superconducting properties are listed.Damped oscillation of the floating capsule in thin helium gas is discussed, and the restoring time is estimated.
基金This work was supported by the National Thousand Talents Program of China, the National Natural Science Foundation of China （Nos. 61473054, 61633006）, and the Fundamental Research Funds for the Central Universities of China （No. DUT15ZD108）.
文摘In this paper, a bias-eliminated subspace identification method is proposed for industrial applications subject to colored noise. Based on double orthogonal projections, an identification algorithm is developed to eliminate the influence of colored noise for consistent estimation of the extended observability matrix of the plant state-space model. A shift-invariant approach is then given to retrieve the system matrices from the estimated extended observability matrix. The persistent excitation condition for consistent estimation of the extended observability matrix is analyzed. Moreover, a numerical algorithm is given to compute the estimation error of the estimated extended observability matrix. Two illustrative examples are given to demonstrate the effectiveness and merit of the proposed method.
基金Beijing Municipal Science&Technology Committee(Z211100003521019).
文摘Introduction To compare the perfusion volumes assessed by a new automated CT perfusion(CTP)software iStroke with the circular singular value decomposition software RAPID and determine its predictive value for functional outcome in patients with acute ischaemic stroke(AIS)who underwent endovascular treatment(EVT).Methods Data on patients with AIS were collected from four hospitals in China.All patients received CTP followed by EVT with complete recanalisation within 24 hours of symptom onset.We evaluated the agreement of CTP measures between the two softwares by Spearman’s rank correlation tests and kappa tests.Bland-Altman plots were used to evaluate the agreement of infarct core volume(ICV)on CTP and ground truth on diffusion-weighted imaging(DWI).Logistic regression models were used to test the association between ICV on these two softwares and functional outcomes.Results Among 326 patients,228 had DWI examinations and 40 of them had infarct volume>70 mL.In all patients,the infarct core and hypoperfusion volumes on iStroke had a strong correlation with those on RAPID(p=0.68 and 0.66,respectively).The agreement of large infarct core(volume>70 mL)was substantial(kappa=0.73,p<0.001)between these two softwares.The ICV measured by iStroke and RAPID was significantly correlated with independent functional outcome at 90 days(p=0.009 and p<0.001,respectively).In patients with DWI examinations and those with an ICV>70 mL,the ICV of iStroke and RAPID was comparable on individual agreement with ground truth.Conclusion The automatic CTP software iStroke is a reliable tool for assessing infarct core and mismatch volumes,making it clinically useful for selecting patients with AIS for acute reperfusion therapy in the extended time window.
